We consider a general equilibrium model where groups operating in a competitive market environment can have several members and make efficient collective consumption decisions. Individuals have the option to leave the group and make it on their own or join another group. We study the effect of...

When formal insurance is unavailable, mutual insurance among households can serve as an alternative. This paper analyzes a game between economic agents facing uncertainty and maximizing discounted utility without enforceable contracts or access to capital markets. While autarky is always a...

We develop a model that combines competitive exchange of private commodities across endogenously formed groups with public good provision and global collective decisions. There is a tension between local and global collective decisions. In particular, we show that group formation and collective...

We study stable matchings on exogenously given or endogenously formed bipartite graphs that reflect constraints on matching. The effects of a change of the exogenously given graph (constraints) are investigated. Specifically, we examine to what extent individuals gain or lose from relaxing...